Has your email address been compromised? Check with Have I been pwned This site will allow you to check if your email address has potentially been compromised.
Remember, you should use different passwords for each site that you log in to. Use a Password manager or your browser to save passwords.
If you must write them down keep that document secure.
Possible Password managers are Lastpass, Keypass or Bitwarden, there are others. Search them out on Google or Bing, if in doubt please contact Mike Watts and I will endeavour to help. Some of the managers are free some of them you will need to pay for.